Playing card

ABSTRACT

A suit and a rank are printed on one surface of a card base sheet, a back pattern is printed on a back surface, an intermediate layer having a black layer or a color layer similar to black is provided on the card base sheet to make transmission of visible rays difficult, and ink containing no carbon is used for printing the suit and the rank, and thus the intermediate layer prevents the transmission of the visible rays from the back surface and the suit and the rank printed with the ink containing no carbon transmit infrared rays, such that it is difficult for both the visible rays and the infrared rays to distinguish the suit and the rank from the back surface, and one set or a plurality of sets of decks are constituted by individual cards cut from the card base sheet by a cutting machine.

BACKGROUND Technical Field

The present invention relates to a playing card.

Related Art

In various playing card games such as poker, baccarat, bridge, andblackjack, a dealer sets playing cards of one deck or a plurality ofdecks on a card shooter and the like, delivers the playing cards one byone from the card shooter, and distributes the playing cards to a gameparticipant. At this time, in order to guarantee fairness of the game,these cards need to be distributed randomly, so a game sponsor needs tosufficiently shuffle the playing cards randomly before setting theplaying cards on the card shooter.

However, when the game sponsor performs shuffling prior to the game, itmay take a long time to shuffle cards, which is a factor of hindering anefficient operation of a game. In addition, when the game sponsorperforms shuffling, there is a problem in that there is room to performfraudulent acts such as inserting and removing cards and replacingcards.

In order to solve such a problem, WO 2009/069708 A discloses shuffledplaying cards individually packaged in a state in which playing cardsconstituting a predetermined number of decks are shuffled. In thepackaging of the shuffled playing card, a shuffled playing card ID foraccessing information, which can specify a shuffle machine or a shufflemachine group shuffling the shuffled playing card, on database isassigned as an ID code.

Originally, in a printing industry, it is essential to use a carbonblack ink in addition to three primary colors, in order to expresssharper and darker black in a black part. Naturally, even in the case ofthe playing card, it is common sense to normally print the black partwith the carbon black ink.

SUMMARY

Carbon has characteristics that infrared emissivity (absorption ratio)is high, so the carbon black ink will appear black when viewed throughan infrared camera.

In recent years, ultra-miniaturization and high performance ofelectronic devices have been advanced, and even the infrared camera withgood performance can be made ultra-miniaturized by malicious fraudulentplayers, so that there is a risk that the camera will be brought fromthe outside into a game hall without being noticed.

When a normal playing card is viewed through an infrared camera withgood performance, a printed part on a front side to which the carbonblack ink is applied can be seen even from a back side of the playingcard. That is, there is a possibility to identify ranks and suits on thefront side when viewed from the back side.

An object of the present invention is to provide a playing card capableof making it difficult to see through a printed part on a front sideeven when the playing card is viewed through an infrared camera.

There is provided a playing card according to an aspect of the presentinvention, wherein a suit and a rank are printed on one surface of acard base sheet, and a back pattern is printed on a back surface of thecard base sheet, the card base sheet has an infrared seeing-throughpreventing layer containing carbon as an intermediate layer, and an inkcontaining no carbon is used to print the suit and the rank, and one setor a plurality of sets of decks are formed by individual cards cut by acutting machine from the card base sheet.

According to this aspect, since the card base sheet is provided with aninfrared seeing-through preventing layer containing the carbon as theintermediate layer, infrared rays radiated from the printed part on thefront side of the card are absorbed by the intermediate layer, andhardly transmit the back side of the card. In addition, since the inkcontaining no carbon is used to print the suit and the rank, adifference between intensity of infrared rays radiated from the printedpart and intensity of infrared rays radiated from an area therearound issmall. Thus, it is extremely difficult to distinguish the suit and therank from a distribution of a trace amount of transmitted infrared rayseven if there are the infrared rays radiated from the printed part onthe front side and the infrared rays transmitting the back side of thecard without being absorbed by the intermediate layer. Therefore, it ispossible to provide a playing card capable of making it difficult to seethrough the printed part on the front side even when the playing card isviewed through the infrared camera.

In the playing card according to the aspect of the present invention,the back pattern on the back surface of the card base sheet may beprinted with an ink containing carbon.

According to the aspect, since the back pattern of the card is printedwith an ink containing carbon, the infrared distribution having the samepattern as the back pattern appears on the back side of the card.Therefore, even if there are the infrared rays radiated from the printedpart on the front side and the infrared rays transmitting the back sideof the card without being absorbed by the intermediate layer, thedistribution of the trace amount of transmitted infrared rays is buriedby overlapping the distribution of the infrared rays radiated from theback pattern of the card, so it is even more difficult to distinguishthe printed part on the front side of the card even when the playingcard is viewed through the infrared camera.

There is provided a playing card according to an aspect of the presentinvention, wherein a suit and a rank are printed on one surface of acard base sheet, and a back pattern is printed on a back surface, thecard base sheet has an infrared seeing-through preventing layercontaining carbon as an intermediate layer, the back pattern on the backside of the card base sheet may be printed with the ink containingcarbon, and one set or a plurality of sets of decks are formed byindividual cards cut by a cutting machine from the card base sheet.

According to this aspect, since the card base sheet is provided with theinfrared seeing-through preventing layer containing the carbon as theintermediate layer, infrared rays radiated from the front side of thecard are absorbed by the intermediate layer, and hardly transmit theback side of the card. In addition, since the back pattern of the cardis printed with the ink containing carbon, the distribution of theinfrared rays having the same pattern as the back pattern appears on theback side of the card. Therefore, even if there are the infrared raysradiated from the printed part on the front side and the infrared raystransmitting the back side of the card without being absorbed by theintermediate layer, the distribution of the trace amount of transmittedinfrared rays is buried by overlapping the distribution of the infraredrays radiated from the back pattern of the card, so it is extremelydifficult to distinguish the suit and the rank from the distribution ofthe infrared rays. Therefore, it is possible to provide a playing cardcapable of making it difficult to see through the printed part on thefront side even when the playing card is viewed through the infraredcamera.

There is provided a playing card according to an aspect of the presentinvention, wherein a suit and a rank are printed on one surface of acard base sheet, and a back pattern is printed on a back surface, an inkcontaining no carbon is used to print the suit and the rank, the backpattern on the back surface of the card base sheet may be printed withthe ink containing carbon, and one set or a plurality of sets of decksare formed by individual cards cut by a cutting machine from the cardbase sheet.

According to the aspect, since the ink containing no carbon is used toprint the suit and the rank, a difference between intensity of infraredrays radiated from the printed part and intensity of infrared raysradiated from an area therearound is small. Thus, it is extremelydifficult to distinguish the suit and the rank from a distribution of atrace amount of transmitted infrared rays even if there are the infraredrays radiated from the printed part on the front side of the card andthe infrared rays transmitting the back side of the card. In addition,since the back pattern of the card is printed with the ink containingcarbon, the distinct uneven distribution of the infrared rays having thesame pattern as the back pattern appears on the back side of the card.Therefore, even if there are the infrared rays radiated from the printedpart on the front side and the infrared rays transmitting the back side,the distribution of the trace amount of transmitted infrared rays isburied by overlapping the distribution of the infrared rays radiatedfrom the back pattern of the card, so it is extremely difficult todistinguish the suit and the rank from the distribution of the infraredrays. Therefore, it is possible to provide a playing card capable ofmaking it difficult to see through the printed part on the front sideeven when the playing card is viewed through the infrared camera.

There is provided a shuffled playing card according to an aspect of thepresent invention, wherein a predetermined sets of playing cards havingany of the above-described characteristics are shuffled by a shufflemachine to form a set of shuffled playing cards, and the set of shuffledplaying cards is individually packaged and sealed.

According to the aspect, it is possible to provide a shuffled playingcard which need not be shuffled by a game sponsor over a long period oftime prior to a game and does not provide any room to perform fraudulentacts such as inserting and removing cards and replacing cards.

In the shuffled playing card according to the aspect of the presentinvention, individually different shuffled playing card IDs may beassigned to the shuffled playing card individually packaged and sealedas ID codes.

According to the aspect, for example, if the shuffled playing card ID isassociated with information that can specify the shuffle machine or ashuffle machine group shuffling the shuffled playing card, the shuffledplaying card ID is assigned to the shuffled playing card individuallypackaged and sealed, and thus when it is conceived that there is anydefect in the playing card and the shuffle machine is a cause of thedefect, it is possible for a manufacturer to easily specify in whichshuffle machine or shuffle machine group the defect occurs, therebymaking it possible to take countermeasures as soon as possible.

In the playing card according to the aspect of the present invention,the different sheet IDs for one card base sheet or each of the pluralityof card base sheets may be printed on the card base sheet, and the sheetID may be printed on a print surface of the card constituting the set ofdecks.

According to this aspect, since the card base sheet on which thedifferent sheet IDs are printed for one card base sheet or each of theplurality of card base sheets is cut to produce the playing card of onedeck or a plurality of decks, it is possible to confirm, on thedatabase, the information on when the card is printed and also when thecard is inspected by tracing back through the distribution history ofthe playing card. As a result, it is possible to confirm whether theplaying card is a genuine product correctly manufactured and distributedby reading the sheet ID from the contents of the card to confirm thehistory on the database even if the contents of the packaged shuffledplaying card are replaced with a set of cards whose arrangement is knownby malicious fraudulent players.

In the playing card according to the aspect of the present invention,the different sheet IDs for one card base sheet or each of the pluralityof card base sheets may be printed on the card base sheet, and the sheetID may be printed on a card other than the card constituting the set ofdecks.

In a shuffled playing card according to the aspect of the presentinvention, the different sheet IDs for one card base sheet or each ofthe plurality of card base sheets may be printed on the card base sheet,the sheet ID may be printed on a print surface of the card constitutingthe set of decks, individually different shuffled playing card IDs areassigned to the shuffled playing card individually packaged and sealedas ID codes, and the sheet IDs of the predetermined sets of cardsconstituting the shuffled playing cards and the shuffled playing cardIDs assigned to the shuffled playing cards may be associated with eachother in database.

There is provided a playing card according to an aspect of the presentinvention, wherein a suit and a rank are printed on one surface of acard base sheet, a back pattern is printed on a back surface, anintermediate layer having a black layer or a color layer similar toblack is provided on the card base sheet to make transmission of visiblerays difficult, and an ink containing no carbon is used for printing thesuit and the rank printing, and thus the intermediate layer prevents thetransmission of the visible rays from the back surface and the suit andthe rank printed with the ink containing no carbon transmit infraredrays, such that it is difficult for both the visible rays and theinfrared rays to distinguish the suit and the rank from the backsurface, and one set or a plurality of sets of decks are constituted byindividual cards cut from the card base sheet by a cutting machine.

In the playing card according to the aspect of the present invention,the back pattern of the card base sheet may be printed with an inkcontaining carbon to allow the ink containing carbon of the back patternto prevent the transmission of the infrared rays from the back surface.

In the playing card according to the aspect of the present invention,the intermediate layer may prevent the infrared rays including thecarbon from seeing-through.

There is provided a shuffled playing card according to an aspect of thepresent invention, wherein predetermined sets of the playing cardshaving any one of the above characteristics may be shuffled by a shufflemachine to form a set of shuffled playing cards.

In the shuffled playing card according to an aspect of the presentinvention, individually different shuffled playing card IDs may beassigned to the shuffled playing cards as ID codes.

A table game system according to an aspect of the present inventionincludes: a playing card having one surface on which a suit and a rankare printed; a game table which performs a game using the playing card;and a card distribution device which withdraws the playing card in thegame table sheet by sheet, wherein the playing card is printed with thesuit and the rank with an ink containing no carbon, and codes indicatingthe suit and the rank are printed with an invisible ink, and the carddistribution device has a function of allowing the code printed with theinvisible ink to read the rank and determining and displaying win orloss results of each game based on the information of the rank.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an exploded view of a playing card according to oneembodiment.

FIG. 2 is an enlarged view of a part of a cross section of the playingcard shown in FIG. 1.

FIG. 3A is a diagram showing a front surface of a card constituting aset of decks among playing cards according to one embodiment, and FIG.3B is a diagram showing a back surface of the card.

FIG. 4A is a diagram showing a front surface of a card other than thecard constituting a set of decks among playing cards according to oneembodiment, and FIG. 4B is a diagram showing a back surface of the card.

FIG. 5 is a flowchart for describing a method of manufacturing a playingcard according to one embodiment.

FIG. 6 is a diagram showing a card base sheet used in the method ofmanufacturing a playing card according to one embodiment, and is adiagram showing a card base sheet on which a sheet ID is printed.

FIG. 7 is a diagram showing a card base sheet used in the method ofmanufacturing a playing card according to one embodiment, and is adiagram showing a modification of a card base sheet on which a sheet IDis printed.

FIG. 8 is a diagram showing a shuffled playing card manufactured by themethod of manufacturing a playing card according to one embodiment, andis a diagram showing the shuffled playing card before a lid of a packageis sealed with a seal.

FIG. 9 is a diagram showing the shuffled playing card according to oneembodiment, and is a diagram showing the shuffled playing card in whicha shuffled playing card ID is assigned to the seal for sealing the lidof the package.

FIG. 10 is a diagram for describing database that stores the shuffledplaying card ID and the sheet ID by associating the shuffled playingcard ID with the sheet ID.

FIG. 11A is a diagram showing a cross section of a conventional playingcard.

FIG. 11B is a diagram showing a cross section of a playing card havingan intermediate layer added to the conventional playing card.

FIG. 11C is a diagram showing a cross section of a playing cardaccording to an embodiment.

FIG. 11D is a diagram showing a cross section of a playing cardaccording to another embodiment.

DETAILED DESCRIPTION

Hereinafter, embodiments of the present invention will be described indetail with reference to the accompanying drawings. In the respectivedrawings, constituent elements having equivalent functions are denotedby the same reference numerals, and the detailed description of theconstituent elements denoted by the same reference numerals is notrepeated.

The table game system according to one embodiment includes a playingcard 2 having a suit 21 a and a rank 21 b printed on one surface thereof(see FIG. 1), a game table which plays a game using the playing card 2,and a card distribution device which withdraws the playing card 2 in thegame table sheet by sheet.

As will be described later, the suit 21 a and the rank 21 b are printedon the playing card 2 with ink containing no carbon. In addition, theplaying card 2 is printed with a code indicating the suit 21 a and therank 21 b with invisible ink (for example, ultraviolet light emittingink which emits light by irradiation of ultraviolet light or DNAcontaining paint which emits light having a specific wavelength withrespect to light).

The card distribution device has a function of allowing the code or therank printed with the invisible ink to read and determining anddisplaying win or loss results of each game based on the information ofthe rank. As the card distribution device, for example, a card shooterdevice described in WO 2012/053179 A or a card shooter device describedin WO 2013/161284 A can be used.

Next, the structure of the playing card 2 according to one embodimentwill be described. FIG. 1 is an exploded view of a playing card 2according to one embodiment. FIG. 2 is an enlarged view of a part of across section of the playing card 2 shown in FIG. 1.

As shown in FIGS. 1 and 2, the playing card 2 according to the presentembodiment has the suit 21 a and the rank 21 b printed on one surfacethereof, a back pattern 29 printed on the back surface thereof, and aninfrared seeing-through preventing layer 28 as an intermediate layer.

In the present embodiment, the infrared seeing-through preventing layer28 as the intermediate layer contains carbon. Since the carbon hascharacteristics that infrared emissivity (absorption ratio) is high, asshown in FIG. 2, the infrared rays irradiated from the printed part (forexample, sheet ID 31 to be described later) of the front surface of thecard are absorbed by the infrared seeing-through preventing layer 28 asthe intermediate layer and hardly transmit the back side of the card. Inthe present specification, the term “visible ray” means radiation thatcan enter the eyes and generate visual sensation and the term “infraredray” means radiation which has a wavelength of a monochromatic lightcomponent longer than that of visible radiation (visible rays) andshorter than about 1 nm, which are based on the definition of JIS Z8120: 2001.

The infrared seeing-through preventing layer 28 is not limited to anaspect including a material such as carbon which absorbs infrared raysas long as it can prevent the transmission of infrared rays. Forexample, the infrared seeing-through preventing layer 28 may be anaspect including a material such as aluminum foil which reflectsinfrared rays.

In the playing card 2 according to the present embodiment, inkcontaining no carbon is used for the printed part of the suit 21 a andthe rank 21 b. The use of the ink containing no carbon is out of commonsense, but since a jet black is not required for the rank and the suitor the pattern of the playing card, there is no problem even if the inkcontaining no carbon is used. Since the ink containing no carbon is usedfor the printed part of the suit 21 a and the rank 21 b, the differencebetween intensity of infrared rays radiated from the printed parts 21 aand 21 b and intensity of infrared rays radiated from an areatherearound is small. Thus, it is extremely difficult to distinguishshapes of the suit 21 a and the rank 21 b from a distribution of a traceamount of transmitted infrared rays even if there are the infrared raysradiated from the printed parts 21 a and 21 b on the front side of thecard and the infrared rays transmitting the back side of the cardwithout being absorbed by the intermediate layer 28.

In the playing card 2 according to the present embodiment, the backpattern 29 of the card is printed with the ink containing carbon (forexample, carbon black ink). For this reason, as shown in FIG. 2, thedistribution of the infrared rays having the same pattern as the backpattern 29 appears on the back side of the card. Therefore, even ifthere are the infrared rays radiated from the printed part (for example,sheet ID 31) on the front side and the infrared rays transmitting theback side of the card without being absorbed by the intermediate layer28, the distribution of the trace amount of transmitted infrared rays isburied by overlapping the distribution of the infrared rays radiatedfrom the back pattern 29 of the card, so it is even more difficult todistinguish the printed part 31 on the front side of the card even whenthe playing card is viewed through the infrared camera.

FIG. 3A is a diagram showing the front surface of the card 21constituting a set of decks among playing cards 2 according to oneembodiment, and FIG. 3B is a diagram showing the back surface of thecard. FIG. 4A is a diagram showing a front surface of a card 22 otherthan the card constituting a set of decks among the playing cards 2according to one embodiment, and FIG. 4B is a diagram showing a backsurface of the card.

As shown in FIGS. 3A and 3B, a set of playing cards 2 according to thepresent embodiment has 4×13=52 cards which are constituted by acombination of four suits 21 a (that is, spade, club, diamond, andheart) and 13 ranks 21 b (that is, ace (A), 2, 3, 4, 5, 6, 7, 8, 9, 10,jack (J), queen (Q), and king (K)) as a card 21 constituting a set ofdecks.

In addition, as shown in FIGS. 4A and 4B, the set of playing cards 2according to the present embodiment further has a “joker” card 22 as acard other than the cards constituting the set of decks. The “joker”card 22 included in one set of playing cards 2 may be one sheet or twosheets. The “joker” card 22 is a card which is removed and discardedbefore a shuffling process at the time of producing a shuffled playingcard to be described later.

The set of playing cards 21 and 22 according to the present embodimentare formed by being individually cut from one card base sheet 20 (seeFIG. 6) by a cutting machine.

As shown in FIGS. 3A and 3B and FIGS. 4A and 4B, common sheet IDs 31 and32 are printed on front surfaces of each of the set of playing cards 21and 22, and a common back pattern 29 is printed on a back side thereof.The sheet IDs 31 and 32 may be a character code including a plurality offigures, alphabets, or symbols, or may be a bar code or atwo-dimensional code in which the character code is encoded.

As shown in FIGS. 3A and 3B, the sheet ID 31 printed on the card 21constituting the set of decks may be printed with ink (for example,transparent UV ink) invisible to human eyes, or may be printed with ink(for example, black ink) visible to human eyes. When the sheet ID 31 isprinted with ink (for example, transparent UV ink) invisible to humaneyes, the appearance becomes similar to that of the conventional card,and thus a user of the card can use the card without feelinguncomfortable. On the other hand, when the sheet ID 31 is printed withink (for example, black ink) visible to the human eyes, although thereis a possibility that the user of the card may feel uncomfortable, thesheet ID 31 is simply an ID code, and therefore it does not causespecial problems in the game.

In addition, as shown in FIGS. 4A and 4B, the sheet ID 32 printed on acard 22 other than the card constituting the set of decks may be printedwith ink (for example, transparent UV ink) invisible to human eyes, ormay be printed with ink (for example, black ink) visible to human eyes.When the card printed with ink (for example, black ink) visible to humaneyes, a manufacturer can easily confirm the sheet ID 32 in themanufacturing process to be described later when inspecting quality ofthe printed card base sheet.

As shown in FIG. 10, the sheet IDs 31 and 32 printed on the respectiveplaying cards 21 and 22 are stored in the database in association withone or both of recording of a printing date of the sheet ID on theoriginal card base sheet 20 and recording of a cut date on theindividual playing cards 21 and 22.

FIG. 8 is a diagram showing a shuffled playing card 12 according to thepresent embodiment, and is a diagram showing the shuffled playing card12 before a package 11 is sealed with a seal 13. FIG. 7 is a diagramshowing the shuffled playing card 12 according to the presentembodiment, and is a diagram showing the shuffled playing card 12 inwhich a shuffled playing card ID 13 a is assigned to the seal 13 forsealing the package 11.

The shuffled playing card 12 according to the present embodiment is acard in which a plurality of decks (for example, four decks or eightdecks) of the card 21 constituting the deck among the above-describedplaying cards 2 are one set, and is sufficiently shuffled by a shufflemachine. In the shuffled playing card 12, different shuffled playingcard IDs 13 a are assigned as ID codes for each set. In the shownexample, the shuffled playing card 12 is housed in a box-shaped package11 and a lid thereof is sealed with a seal 13. The shuffled playing cardID 13 a is encoded as a bar code and printed on the seal 13 which sealsthe package 11.

As shown in FIG. 8, the sheet ID 31 of the playing card 21 constitutingthe shuffled playing card 12 and the shuffled playing card ID 13 a arestored in the database in association with each other. In addition, inthe example shown in FIG. 10, the shuffled playing card ID 13 a and ashuffle machine ID and a shuffle date which specify a shuffle machine ora shuffle machine group shuffling the shuffled playing card 12 arestored in database in association with each other.

Next, a method of manufacturing a playing card 2 and a shuffled playingcard 12 according to the present embodiment will be described. FIG. 5 isa flowchart showing a method of manufacturing a playing card 2 and ashuffled playing card 12 according to the present embodiment.

In the manufacturing process of the playing card 2 and the shuffledplaying card 12 according to the present embodiment, it is preferablefor a process management system to consistently perform processmanagement from order to shipment. In the present embodiment, amanufacturing method using such a process management system will bedescribed.

First, the card base sheet 20 having the infrared seeing-throughpreventing layer 28 as the intermediate layer is prepared. As shown inFIGS. 5 and 6, as a printing process, the printing machine prints thesuit 21 a and the rank 21 b on the front surface of the card base sheet20, and prints the back pattern 29 on the back surface thereof (stepS40). In the present embodiment, the ink containing no carbon is usedfor printing the suit 21 a and the rank 21 b. In addition, the inkcontaining carbon is used for printing the back pattern 29.

In the example shown in FIG. 6, a total of 56 cards including 52 cards21 including a combination of four suits and 13 ranks, one “joker” card22, and three other cards 23 are printed in a matrix arrangement of 8rows×7 columns.

As one modification, as shown in FIG. 7, a total of 105 cards includingtwo decks of 52 cards 21 including a combination of four suits and 13ranks and one other card 23 may be printed in a matrix arrangement of 7rows×15 columns.

Next, as a sheet ID assigning step, the process management systemassigns different sheet IDs to each card base sheet or the plurality ofcard base sheets and the printing machine prints the sheet IDs 31 and 32on the front surface of the card base sheet 20 (step S41). In addition,by the process management system, the sheet IDs 31 and 32 and theprinting dates of the sheet IDs 31 and 32 on the card base sheet 20 arestored in the database in association with each other (see FIG. 10).Although not shown in the drawing, the sheet IDs 31 and 32 may be storedin the database in association with one or two or more of a factoryname, a manufacturing line, a customer name (casino name).

In the present embodiment, the sheet ID 31 is printed on the card 21constituting a set of decks with ink (for example, transparent UV ink)invisible to human eyes. As a result, the card 21 constituting the setof decks has the same appearance as a conventional card, and thus theuser of the card can use the card without feeling uncomfortable. Itshould be noted that the sheet ID 31 may be printed only on a specificcard (for example, spade A) among the cards 21 constituting the set ofdecks, or may be printed on all the cards.

On the other hand, the sheet ID 32 is printed on the cards 22 and 23other than the card constituting the set of decks with ink (for example,black ink) visible to human eyes. As a result, when the manufacturer caneasily confirm the sheet ID when inspecting the quality of the printedcard base sheet.

In the present embodiment, the sheet ID assigning process (step S41) isperformed after the printing process (step S40), but the presentembodiment is not limited thereto, and the printing process (step S40)may be performed after the sheet ID assigning process (step S41).

Next, the card base sheet 20 having undergone the printing process (stepS40) and the sheet ID assigning process (step S41) is cut intoindividual cards 21, 22, and 23 by the cutting machine (step S42). Byremoving cards 22 and 23 other than the cards constituting the set ofdecks from the cut card, the playing card 21 corresponding to one deck(corresponding to two decks from the card base sheet 20 shown in FIG. 7)is produced.

The sheet ID 31 is read from the playing card 21 constituting the set ofdecks by the process management system before being shuffled or duringbeing shuffled by the shuffle machine to be described later and isstored in the database in association with the shuffle machine (orshuffle machine group) and shuffled date and time (see FIG. 10).

Next, as the shuffling process, the plurality of decks (for example,four decks or eight decks) of playing card 21 are shuffled by theshuffle machine, and the set of shuffled playing cards 12 is produced(step S43). As the shuffle machine, for example, the shuffle machinedescribed in WO 2009/069708 A can be used.

Next, the set of shuffled playing cards 12 which has undergone theshuffling process (step S43) is packaged by a packaging machine (stepS44). In the present embodiment, as shown in FIG. 8, the set of shuffledplaying cards 12 is housed in the box-shaped package 11. The material ofthe package 11 is not particularly limited, and may be paper or a resinfilm. As shown in FIG. 7, the lid of the package 11 is sealed with theseal 13.

Next, different shuffled playing card IDs are generated for each set ofshuffled playing cards by the process management system, and theshuffled playing card ID 13 a is assigned to the set of shuffled playingcards 12 as the ID code (step S45). In the shown example, the shuffledplaying card ID 13 a is encoded as the bar code and is printed on theseal 13 sealing the lid of the package 11 by the printing machine.

In the shown example, in addition to the shuffled playing card ID 13 a,a specification table 13 b is printed on the seal 13. For example,arbitrary information such as a manufacturing number, a product number,a product name, a color, and a manufacturing date of the shuffledplaying card is described in the specification table 13 b.

Further, by the process management system, the sheet ID 31 read from theplaying card 21 constituting the set of decks before the shufflingprocess (step S43) is stored in the database in association with theshuffled playing card ID 13 a of the set of shuffled playing cards 12 towhich the deck belongs (see FIG. 10). In the shown example, the set ofshuffled playing cards 12 are configured from the playing cards 21corresponding to four decks, and four sheet IDs 31 are stored in thedatabase in association with each shuffled playing card ID 13 a. Inaddition, by the process management system, in the database, theshuffled playing card ID 13 a and the shuffle machine ID and the shuffledate which specify the shuffle machine or the shuffle machine groupshuffling the shuffled playing card 12 are stored in the database inassociation with each other.

According to the present embodiment, as shown in FIG. 1, since the cardbase sheet 20 is provided with the infrared seeing-through preventinglayer 28 containing the carbon as the intermediate layer, the infraredrays radiated from the printed part on the front side of the card areabsorbed by the intermediate layer 28, and hardly transmit the back sideof the card. In addition, since the ink containing no carbon is used toprint the suit 21 a and the rank 21 b, a difference between intensity ofinfrared rays radiated from the printed part and intensity of infraredrays radiated from an area therearound is small. Thus, it is extremelydifficult to distinguish the suit 21 a and the rank 21 b from adistribution of a trace amount of transmitted infrared rays even ifthere are the infrared rays radiated from the printed part on the frontside of the card and the infrared rays transmitting the back side of thecard without being absorbed by the intermediate layer 28. Therefore, itis possible to provide a playing card 2 capable of making it difficultto see through the printed part on the front side even when the printedpart on the front side is viewed through the infrared camera.

In addition, according to the present embodiment, since the back pattern29 on the back surface of the card base sheet 20 is printed with the inkcontaining carbon, as shown in FIG. 2, the distribution of the infraredrays having the same pattern as the back pattern 29 appears on the backside of the card. Therefore, even if there are the infrared raysradiated from the printed part on the front side and the infrared raystransmitting the back side of the card without being absorbed by theintermediate layer 28, the distribution of the trace amount oftransmitted infrared rays is buried by overlapping the distribution ofthe infrared rays radiated from the back pattern 29 of the card, so itis even more difficult to distinguish the printed part on the front sideof the card even when the playing card is viewed through the infraredcamera.

In addition, according to the present embodiment, since thepredetermined sets of playing cards 2 described above are shuffled bythe shuffle machine to form a set of shuffled playing cards 12 and a setof shuffled playing cards 12 is packaged and sealed individually, it ispossible to provide a shuffled playing card which need not be shuffledby a game sponsor over a long period of time prior to a game and doesnot provide any room to perform fraudulent acts such as inserting andremoving cards and replacing cards.

In addition, according to the present embodiment, since differentshuffled playing card IDs 13 a are individually assigned, as ID codes,to the shuffled playing card 12 individually packaged and sealed, forexample, as shown in FIG. 10, if the shuffled playing card ID 13 a isassociated with information that can specify the shuffle machine or theshuffle machine group shuffling the shuffled playing card 12, when it isconceived that there is any defect in the playing card and the shufflemachine is a cause of the defect, it is possible for a manufacturer toeasily specify in which shuffle machine or shuffle machine group thedefect occurs, thereby making it possible to take countermeasures assoon as possible.

In addition, according to the present embodiment, since the card basesheet 20 on which the different sheet ID 31 are printed for one cardbase sheet 20 or each of the plurality of card base sheets 20 is cut toproduce the playing card of one deck or a plurality of decks, it ispossible to confirm, on the database, the information on when the cardis printed and also when the card is inspected by tracing back throughthe distribution history of the playing card 21. As a result, it ispossible to confirm whether the playing card is a genuine productcorrectly manufactured and distributed by reading the sheet ID 31 fromthe contents of the card to confirm the history on the database in unitsof sheet even if the contents of the packaged shuffled playing card 12are replaced with a set of cards whose arrangement is known by maliciousfraudulent players.

In addition, by printing different sheet IDs 31 for each card base sheet20 or the plurality of card base sheets 20, the ID management of thecard base sheet 20 in the factory becomes possible. For example, evenwhen the card base sheet 20 is discarded halfway, it is possible tomanage at which step the playing card is discarded in the database. Inthis way, it is possible to grasp a yield in each process at themanufacturing stage. In addition, it will be able to be understoodwhether the card of the card base sheet which is determined to bedefective in each process and thus discarded is inadvertently mixed ingoods (that is, it will be able to be understood whether only cards ofgood card base sheet are used for goods). In addition, even if maliciousfraudulent players illegally obtain the discarded card base sheet 20 andcut the obtained card base sheet by themselves to produce a counterfeitcard and bring the produced counterfeit card for use in a game, thesheet ID 31 is read from the card to confirm the history on thedatabase, thereby making it possible to easily detect that the playingcard is a counterfeit card and enhance the security of the game.

In addition, in the above-described embodiment, in the sheet IDassigning step, as shown in FIGS. 6 and 7, the sheet IDs 31 and 32 areprinted on a part of the card base sheet 20 on which the cards 21 to 23are printed, but the present embodiment is not limited thereto, and thesheet ID may also be printed on a part of the card base sheet 20 onwhich the card is not printed. In this case, it is possible to acquirethe sheet ID from the remaining part (so-called punching scrap) afterremoving the cards 21 to 23 from the card base sheet 20.

In addition, in the above-described embodiment, (1) in addition to thefact that the card base sheet 20 has the infrared seeing-throughpreventing layer 28 as the intermediate layer, (2) the ink containing nocarbon is used to print the suit 21 a and the rank 21 b, (3)furthermore, the back pattern 29 on the back surface of the card basesheet 20 is printed with the ink containing carbon, but (1) in additionto the fact that the card base sheet 20 has the infrared seeing-throughpreventing layer 28 as the intermediate layer, (2) when the inkcontaining no carbon is used to print the suit 21 a and the rank 21 b,(3) the back pattern 29 on the back surface of the card base sheet 20 isnot necessarily printed with the ink containing carbon, and the backpattern 29 may also be printed with the ink containing no carbon.

(1) In addition to the fact that the card base sheet 20 has the infraredseeing-through preventing layer 28 as the intermediate layer, (3) whenthe back pattern 29 on the back surface of the card base sheet 20 isprinted with the ink containing carbon, (2) the ink containing no carbonis not necessarily used to print the suit 21 a and the rank 21 b, andthe ink containing carbon may also be used to print the suit 21 a andthe rank 21 b. Even in such an aspect, (1) since the card base sheet 20is provided with the infrared seeing-through preventing layer 28containing carbon as the intermediate layer, the infrared rays radiatedfrom the front side of the card is absorbed by the intermediate layer 28and hardly transmit the back side thereof, (3) furthermore, since theback pattern 29 of the card is printed with the ink containing carbon,the distribution of the infrared rays having the same pattern as theback pattern 29 appears on the back side of the card. Therefore, even ifthere are the infrared rays radiated from the printed parts 21 a and 21b on the front side and the infrared rays transmitted on the back sidewithout being absorbed by the intermediate layer 28, the distribution ofthe trace amount of transmitted infrared rays is buried by overlappingthe distribution of the infrared rays radiated from the back pattern 29of the card, so it is extremely difficult to distinguish the suit 21 aand the rank 21 b from the distribution of the infrared rays. Therefore,even in the aspect, it is possible to provide a playing card capable ofmaking it difficult to see through the printed part on the front sideeven when the playing card is viewed through the infrared camera.

Further, (2) the ink containing no carbon is used to print the suit 21 aand the rank 21 b, and (3) furthermore, when the back pattern 29 on theback surface of the card base sheet 20 is printed with the inkcontaining carbon, (1) the card base sheet 20 does not necessarily havethe infrared seeing-through preventing layer 28 as the intermediatelayer, and the card base sheet 20 may not have the infraredseeing-through preventing layer 28 as the intermediate layer. Even inthe aspect, since (2) the ink containing no carbon is used to print thesuit 21 a and the rank 21 b, the difference between intensity ofinfrared rays radiated from the printed part and intensity of infraredrays radiated from an area therearound is small. For example, it isextremely difficult to distinguish the suit 21 a and the rank 21 b froma distribution of a trace amount of transmitted infrared rays even ifthere are the infrared rays radiated from the printed part on the frontside of the card and the infrared rays transmitting the back side of thecard. In addition, since the back pattern 29 of the card is printed withthe ink containing carbon, the distribution of the infrared rays havingthe same pattern as the back pattern 29 appears on the back side of thecard. Therefore, even if there are the infrared rays radiated from theprinted part on the front side and the infrared rays transmitting theback side, the distribution of the trace amount of transmitted infraredrays is buried by overlapping the distribution of the infrared raysradiated from the back pattern 29 of the card, so it is extremelydifficult to distinguish the suit 21 a and the rank 21 b from thedistribution of the infrared rays. Therefore, even in the aspect, it ispossible to provide a playing card capable of making it difficult to seethrough the printed part on the front side even when the playing card isviewed through the infrared camera.

FIG. 11A is a diagram showing a cross section of a conventional playingcard 111. Since visible rays 103 and infrared rays 104 transmit theconventional playing card 111, there was a problem in that it ispossible to distinguish printing 131 indicating a rank or a suit fromthe back surface.

FIG. 11B is a diagram showing a cross section of a playing card 112having an intermediate layer 128 added to the conventional playing card111. The playing card 112 includes the intermediate layer 128 having ablack layer or a color layer similar to black to prevent thetransmission of the visible rays 103 and make it difficult for thevisible rays 103 to distinguish the printing 131 indicating the rank orthe suit from the back surface. However, since the infrared rays 104have a strong transmitting force and transmit the intermediate layer128, there was a problem in that the printing 131 indicating the rank orthe suit still can be distinguished from the back surface by using theinfrared rays 104.

FIG. 11C is a diagram showing a cross section of a playing card 113according to an embodiment. The playing card 113 according to thepresent embodiment includes the intermediate layer 128 having the blacklayer or the color layer similar to black, and furthermore, the inkcontaining no carbon is used for printing 132 indicating a rank or asuit. First, the playing card 112 includes the intermediate layer 128having a black layer or a color layer similar to black to prevent thetransmission of the visible rays 103 and make it difficult for thevisible rays 103 to distinguish the printing 132 indicating the rank orthe suit from the back surface. The infrared rays 104 transmit theintermediate layer 128, but furthermore, the ink containing no carbon isused for the printing 132 indicating the rank or the suit, so theinfrared rays 104 transmit the printing 132 indicating the rank or thesuit and it is difficult for even the infrared rays 104 to distinguishthe printing 132 indicating the rank or the suit from the back surface.As described above, in the playing card 113 according to the presentembodiment, it is difficult for both of the visible rays 103 and theinfrared rays 104 to distinguish the printing 132 indicating the rank orthe suit from the back surface.

FIG. 11D is a diagram showing a cross section of a playing card 114according to another embodiment of the present invention. The playingcard 114 according to another embodiment includes an intermediate layer129 having a black layer or a color layer similar to black, andfurthermore, the ink containing no carbon is used for the printing 132indicating the rank or the suit. In addition, the intermediate layer 129contains carbon. The intermediate layer 129 having the black layer orthe color layer similar to black prevents the transmission of thevisible rays 103, and the intermediate layer 128 containing the carbonreduces the transmission amount of the infrared rays 104. The infraredrays 104 do not completely stop at the intermediate layer 129 and someof the infrared rays transmit the intermediate layer 129, butfurthermore, the ink containing no carbon is used for the printing 132indicating the rank or the suit, so the infrared rays 104 transmit theprinting 132 indicating the rank or the suit and it is difficult foreven the infrared rays 104 to distinguish the printing 132 indicatingthe rank or the suit from the back surface. As described above, theplaying card 114 of another embodiment of the present invention furtherreduces the amount of the infrared rays 104 transmitting theintermediate layer 129 than the playing card 113, so it is difficult forboth of the visible rays 103 and the infrared rays 104 to distinguishthe printing 132 indicating the rank or the suit from the back surface.

The above-described embodiments are described for the purpose ofenabling those skilled in the art to which the present invention belongsto implement the present invention. Various modifications of the aboveembodiments are obvious to those skilled in the art, and the technicalidea of the present invention can be applied to other embodiments.Accordingly, the present invention is not limited to the embodimentsdescribed, but should be the broadest scope in accordance with thetechnical idea defined by the claims. The constituent elements of theabove-described embodiments and individual modifications can bearbitrarily combined without departing from the gist of the invention.

1. A playing card, wherein: a suit and a rank are printed on one surfaceof a card base sheet, and a back pattern is printed on a back surface,an intermediate layer having a black layer or a color layer similar toblack is provided on the card base sheet to make transmission of visiblerays difficult, and an ink containing no carbon is used for printing thesuit and the rank, the intermediate layer prevents the transmission ofthe visible rays from the back surface and the suit and the rank printedwith the ink containing no carbon transmit infrared rays, such that itis difficult for both the visible rays and the infrared rays todistinguish the suit and the rank from the back surface, and one set ora plurality of sets of decks are constituted by individual cards cutfrom the card base sheet by a cutting machine.
 2. The playing cardaccording to claim 1, wherein the back pattern of the card base sheet isprinted by an ink containing carbon to allow the ink containing carbonof the back pattern to prevent the transmission of the infrared raysfrom the back surface.
 3. The playing card according to claim 1, whereinthe intermediate layer prevents the infrared rays including the carbonfrom seeing-through.
 4. A shuffled playing card, wherein predeterminedsets of the playing cards according to claim 1 are shuffled by a shufflemachine to form one set of shuffled playing cards.
 5. The shuffledplaying card according to claim 4, wherein individually differentshuffled playing card IDs are assigned to the shuffled playing cards asID codes.
 6. A table game system, comprising: a playing card having onesurface on which a suit and a rank are printed; a game table forperforming a game using the playing card; and a card distribution devicefor withdrawing the playing card in the game table sheet by sheet,wherein: the playing card is printed with a suit and a rank with an inkcontaining no carbon, and codes indicating the suit and the rank areprinted with an invisible ink, and the card distribution device has afunction of reading the rank from the code printed with the invisibleink and determining and displaying win or loss results of each gamebased on information of the rank.